The laboratory of in vitro marrow culture is concerned with granulopoiesis. The laboratory has been examining the effect of 41.8 degrees C with and without doxorubicin, or nitrosourea on human bone marrow (CFU-C), human peripheral blood (CFU-PB) and on normal murine marrow CFU-C. Also this laboratory assays and correlates data from international laboratories testing NCI-Abbott human colony stimulating factor (HGCSF). Future projects include correlation of the combined effects of nitrosourea plus hyperthermia on murine CFU-C compared to a murine mammary tumor. The laboratory will also assay bone marrow and peripheral CFU-C, as well as serum CSF for a proposed clinical trial of NCI-Abbott HGCSF in smoldering leukemia and aplastic anemia. Trials of the photometric macrotube scanner to enumerate CFU-C continue.